nirajt said:
i am trying to make an electronic target for air-rifle shooting contests. the circular target is to have an approximate diameter of 1.5 inches with 10 equidistant rings inside it. each ring is a disinct score.
my main problem is a low cost sensor for the application.
kindly advice.
how about aluminum foil and tissue paper
first cut a sheet of tissue paper and foil the maximum size of your target.
now cut rings out of your foil, the more accurate you cut them, the closer you can space the rings, without them touching
then make a sandwich with your rings and the tissue paper, use as little glue as possible, since it'll make the target too stiff
idea is, as the projectile impacts the target, it will 'blow through' the thin foil and paper, and cause the ring to short to the large foil backplane. each ring could be connected to some sort of indicator, a counter or a microcontroller (whatever you feel like). and the large foil backplane could just be ground or a postive supply rail or whatever.
the targets should be really cheap to make, other than the cost of your time to assemble them. maybe you've know some little kids that can help you with your 'craft project' cutting out the rings
the target could be made to last a while by using high voltage or high current, so that the small amount of foil that makes contact is burned away when it shorts, so the short only lasts briefly enough to register on the counter, before going 'open'